I'm an avid sci-fi reader and one of the most interesting things to do is go back and read old books in the genre. A lot of authors seem to conceptualize the future from their time-point using modified versions of their current technology.
For example I read a series called "Med Ship Man" (originally released in 1963) once where all travel was via rocket. Granted, they had some inexplicable way to travel faster than light and had a gravity driven device that raised and lowered ships, but the bullet-design was very obvious.
Another series I just finished reading was "The Creatures of Man" which came out in 1952. In this series, man did not use ships to travel the stars. Instead they created molecular devices (nanites in our language) that protected their bodies from deep-space travel, powered distance-warping systems, kept them warm, oxygenated, allowed them to eat, sleep, communicate and even protected them during re-entry.
I don't know that any of these projections into the future are valid. Personally, I can only be somewhat assured that in 100 years, humanity may still exist and may have figured out ways to go really really really fast (insert ludicrous speed joke here).
no jokes we are in serious area. we have right to dream
for me i tkink about human body regeneration, increasing longevity ( yeah, having 200 years old & stay in good health. and may be still dredge young sweet girl or start to do that : it's a difficult)
there are also genetic engineering , stem cell application (changing organs like a machine , having a big one ...)
creating a new species of human with nano-technology like cyborg (half human half machine)
also space exploration
well there are many areas where man has not done any research
but all this would be done in future